5. Determination of the Chromium.—See Analysis of Chrome-
6. Determination of the Tungsten.—The tungsten is first separated
as tungstic acid on the lines indicated for the analysis of tungsten steels
(see p. 188) and the nickel in the filtrate estimated by the method given
Nickel steels usually contain 0-5-10% Ni but the content may reach 25%,
especially in steels for armour-plating, or even more (invar contains 46% Ni
and 0-15% C). Chromium is often associated with the nickel (chrome-nickel
The following results are given by Geiger:
Composition of Nickel Steels (percentages)
Nickel Steel for
Ball mills ......
Gun barrels (American) .
Toothed wheels ....
Manganese steels are valued for their hardness and strength, and have
properties analogous to those of nickel steels and are less costly. From
the analytical standpoint they may be regarded as ordinary steels very rich
1. Determination of Silicon and Manganese.—2-5 grams of the
sample are treated with nitric acid (D 1-18) and the liquid evaporated to
dryness, calcined, and taken up in hydrochloric acid, the solution being
again evaporated and the residue heated at 135° to render the silica com-
pletely insoluble. The subsequent procedure is as indicated on p. 172.
The filtrate is collected in a measuring flask and the manganese present
determined either by Volhard's volumetric method or electrolytically (see
2. Determination of the Carbon, Phosphorus and Sulphur.—
See Iron, i, 4, 5.
The percentage compositions of certain manganese steels in common use are
(Geiger) :lied by 0-2032 gives the amount